Your motherboard does not officially support it, in the same way that your CPU does not officially support being run at speeds higher than its stock setting. By exceeding the motherboard's rating, you're overclocking it, just like you would a CPU or a video card. It doesn't necessarily mean the motherboard isn't capable of it, but it does mean that you may have to do some tweaking to get it to run.

ahh fair enough, such as voltage and what not, but for a q6600 to reach 3.5-3.6 the best ratio would be 500x7 with my ram? is this the only way to have my ram run at its potential or even overclock it?

what i dont understand is why does my motherboard support such high ram frequences yet has an fsb wall of 1600